CSF and Ventricles

Question 1

What is communicating (non-obstructive hydrocephalus)

Answer 1

No blockage, ventricles are talking to eachother

Overproduction of CSF (rare)

Under-absorption of CSF

if all ventricles are enlarged, think absorption issue

Question 2

What is noncommunicating or obstructive hydrocephalus

Answer 2

Something is blocking the ventricles, they are not talking to eachother

Obstruction of outflow.

Stenosis or narrowing

Question 3

Describe pathway of CSF in general

Answer 3

Lateral-> foramina of Monroe-> 3rd-> cerebral aqueduct ->4th-> lateral and medial apperture-> subarachnoid space

Question 4

Describe pathway of CSF made by the choroid plexus in 4th and lateral ventricles

Answer 4

4th and lateral ventricles -> lateral and medial aperture -> subarachnoid space -> reabsorbed by arachnoid granulations -> drains into dural venous sinuses

Question 5

Communicating (nonobstructing) hydrocephalus diseases

Answer 5

Normal pressure hydrocephalus

Question 6

Noncomunicating (obstructive) hydrocephalus diseases

Answer 6

Aqueductal stenosis
Dandy walker
Chiari II

Question 7

What is normal pressure hydrocephalus

Answer 7

Communicating nonobstructive hydrocephalus

Enlarged ventricles and cortical atrophy bc CSF isn’t draining due to CSF viscosity, elastic ventricular walls, or impaired CSF absorption)

TRIAD: wacky, wobbly, wet

Question 8

What is aqueductal stenosis

Answer 8

Noncommunicating obstructive hydrocephalus.

Causes: X-linked congenital, pineal tumor, meningitis, intrauterine inflammation

CSF accumulates in lateral and 3rd ventricles due to cerebral aqueduct stenosis

Sx: HA, visual issues, vomiting, photophobias, lethargy

Question 9

What is Dandy Walker

Answer 9

Noncommunicating obstructive hydrocephalus

Causes: congential brain malformation in 13th-18th wk

CSF accumulates above 4th ventricle due to 4th ventricular outlet obstruction. Cerebellar hypoplasia secondary to cyst

Sx: bulging head, vomiting, issues with movement milestones

Question 10

What is Chiari II Malformation

Answer 10

Noncommunicating obstructive hydrocephalus

Inferior cerebellar tonsils and vermis displace downward thru foramen magnum. Fluid above 4th ventricle. Associated w/ myelomeningocele

Sx: feeding issues, slow noisy breathing, gagging drooling, issues with movement, club foot possibly

Question 11

What are “take-homes” on hydrocephalus?

Answer 11

Proximal to obstruction = problem will enlarge

If all ventricles are enlarged, think about absorption issue.